Hinged, weighted handgrip with magnetic engagement system

ABSTRACT

A handgrip for use with a dumbbell is provided. The dumbbell includes a handgrip top and a handgrip bottom that are connected with a handgrip hinge. A dumbbell is secured within the handgrip by placing the handle of the dumbbell into a bottom foam engagement structure in the handgrip bottom, then the handgrip top is rotated into contact with the handgrip bottom using the handgrip hinge until the handgrip reaches a closed position wherein the handgrip top is in contact with the handgrip bottom. In the closed position, a top foam engagement structure of the handgrip top is also engaging the handle of the dumbbell and opposing magnets positioned in the handgrip top and handgrip bottom magnetically engage each other to help keep the handgrip in the closed position.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional Application No. 63/256,215, filed Oct. 15, 2021, entitled “WEIGHTED HAND GRIPS”, which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

The present invention generally relates to exercise equipment. More particularly, the present invention relates to a weighted handgrip for use with a dumbbell.

Many commercial gyms provide a series of dumbbells of increasing weights for use by their members. However, the most typical progression of dumbbell weights in a commercial gym setting is every 5 pounds and it may not be possible for a gym-goer to traverse such a sizable increase in weight.

BRIEF SUMMARY OF THE INVENTION

One or more of the embodiments of the present invention provide a handgrip for use with a dumbbell. The dumbbell includes a handgrip top and a handgrip bottom that are connected with a handgrip hinge. Both the handgrip top and handgrip bottom include two end flanges connected by a grip structure having a cylindrical interior describing a foam engagement structure. A dumbbell handle may be placed in the foam engagement structure of the handgrip bottom and the handgrip top may be rotated into contact with the handgrip bottom using the handgrip hinge so that the foam engagement structure of the handgrip top is also in contact with the dumbbell handle. Additionally, the handgrip top and handgrip bottom include opposing magnets that magnetically engage each other to help keep the handgrip in the closed position.

A first use for the present handgrip is in conjunction with pre-existing dumbbells to provide to the user a small but gradual increase in weight lifted. This allows the lifter to further challenge their body in small increments and may be helpful to maximize strength, efficiency, and or hypertrophy. For example, the present handgrip may be constructed to weigh 1.0 lb or 2.5 lbs so that a gym-goer attempting to transition from a 30 lbs dumbbell to a 35 lbs dumbbell may instead transition upward in stages from 30 to 31 or 32.5 and then to 35 lbs.

A second use for the present handgrip is to reduce the total number of weights that may be needed, for example in a home gym setting, while still providing a user with many available weights. For example, if a user possesses handgrips with weights of 2.5 lbs, 5.0 lbs, and 7.5 lbs, then the user may simply purchase five dumbbells with weights of 10 lbs, 20 lbs, 30 lbs, 40 lbs, and 50 lbs, but can use the handgrips to work out at any weight from 2.5 lbs to 57.5 lbs by either using the handgrips alone or by combining the handgrips with the five dumbbells.

A third use for the present handgrip 100 is to avoid touching dumbbell handles in a commercial gym setting so as to lessen exposure to germs that may be present on the dumbbell handles.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exploded view of a hinged, weighted handgrip with magnetic engagement system according to an embodiment of the present invention.

FIG. 2 illustrates a right side view of the handgrip of FIG. 1 in the closed position according to an embodiment of the present invention.

FIG. 3 illustrates a left side view of the handgrip of FIG. 1 near the fully open position according to an embodiment of the present invention.

FIG. 4 illustrates a top view of the handgrip of FIG. 1 in the closed position according to an embodiment of the present invention.

FIG. 5 illustrates a sectional view of the handgrip of FIG. 4 sectioned between the indicators 5-5 shown in FIG. 4 .

FIG. 6 illustrates a perspective view of the handgrip of FIG. 1 with a dumbbell positioned in the handgrip according to an embodiment of the present invention.

FIG. 7 illustrates a front view of the handgrip of FIG. 1 with a dumbbell positioned in the handgrip in the closed position.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates an exploded view of a hinged, weighted handgrip with magnetic engagement system 100 according to an embodiment of the present invention. The handgrip 100 includes a handgrip top 105 and a handgrip bottom 150 that are connected with a handgrip hinge 195 including left hinge pin 197 and right hinge pin 198. The handgrip top 105 includes a top left flange 110, a top right flange 120, a top grip structure 130, a top foam engagement structure 140, a top foam channel 142, and a top-to-bottom handgrip contact surface 144.

The top left flange 110 includes a top left flange first flat region 111, a top left flange second flat region 112, a top left flange third flat region 113, a top left flange pry structure 114, a top left flange hinge pin insert aperture 115, a top left flange hinge rotation stop 116, a top left flange magnet insert aperture 117, and a top left flange magnet 119.

The top right flange 120 includes a top right flange first flat region 121, a top right flange second flat region 122, a top right flange third flat region 123, a top right flange pry structure 124, a top right flange magnet insert aperture 127 and a top right flange magnet 129. A top right flange hinge rotation stop 126 and a top right flange hinge pin insert aperture 125 are also included in the top right flange 120 and mirror their counterpart structures in the top left flange 110, but are not shown in FIG. 1 .

The handgrip bottom 150 includes a bottom left flange 160, a bottom right flange 170, a bottom grip structure 180, and a bottom foam engagement structure 190, a bottom foam channel 182, and a bottom-to-top handgrip contact surface 184.

The bottom left flange 160 includes a bottom left flange first flat region 161, a bottom left flange second flat region 162, a bottom left flange third flat region 163, a bottom left flange pry structure 164, a bottom left flange hinge pin insert aperture 165, a bottom left flange hinge rotation wall 166, a bottom left flange magnet insert aperture 167, and a bottom left flange magnet 169.

The bottom right flange 120 includes a bottom right flange first flat region 171, a bottom right flange second flat region 172, a bottom right flange third flat region 173, a bottom right flange pry structure 174, a bottom right flange magnet insert aperture 177, and a bottom right flange magnet 179. A bottom right flange hinge rotation wall 176 and a bottom right flange hinge pin insert aperture 175 are also included in the bottom right flange 170 and mirror their counterpart structures in the bottom left flange 110, but are not shown in FIG. 1 .

The bottom foam engagement structure 190 includes a full-width foam pad 191, a first end pad 192, and a second end pad 193.

In assembling the handgrip 100, the full width foam pad 191 is adhered to the bottom foam channel 182. Next, the first end pad 192 and second end pad 193 are adhered to the full width foam pad 191 to form the bottom foam engagement structure 190. Additionally, the top foam engagement structure 140 is adhered to top foam channel 142. Also, the top left flange magnet 119 is inserted into and adhered to the top left flange magnet insert aperture 117, the top right flange magnet 129 is inserted into and adhered to the top right flange magnet insert aperture 127, the bottom left flange magnet 169 is inserted into and adhered to the bottom left flange magnet insert aperture 167, and the bottom right flange magnet 179 is inserted into and adhered to the bottom right flange magnet insert aperture 177.

Additionally, the handgrip hinge 195 is formed by inserting the left hinge pin 197 into both the top left flange pin insert aperture 115 and the bottom left flange hinge pin insert aperture 165 and inserting the right hinge pin 198 into both the top right flange pin insert aperture 125 and the bottom right flange hinge pin insert aperture 175. Each hinge pin 197, 198 may be adhered to affixed to the handgrip top 105 to allow the handgrip bottom 150 to rotate around the hinge pin 197, 198, or the hinge pin 197, 198 may be adhered to affixed to the handgrip bottom 150 to allow the handgrip top 105 to rotate around the hinge pin 197, 198.

The use of the left hinge pin 197 and right hinge pin 198 join the handgrip top 105 and handgrip 150 and allow the handgrip top 105 and handgrip bottom 150 to rotate relative to each other from a closed position to a fully open position.

In the closed position, the top-to-bottom handgrip surface 144 of the handgrip top 105 and the bottom-to-top handgrip contact surface 184 of the handgrip bottom 150 are in contact. Additionally, the top left flange magnet 119 and top right flange magnet 129 are positioned to be level with the bottom-most surface of the handgrip top 105 and thus also form part of the top-to-bottom handgrip surface 144. Similarly, the bottom left flange magnet 169 and bottom right flange magnet 179 are positioned to be level with the top-most surface of the handgrip bottom 150 and thus also form part of the bottom-to-top handgrip surface 184. Consequently, then the handgrip 100 is in the closed position, the top left flange magnet 119 is in magnetic engagement with the bottom left flange magnet 169 and the top right flange magnet 129 is in magnetic engagement with the bottom right flange magnet 179.

In the fully open position, the handgrip top 105 and handgrip bottom 150 are rotated around the hinge pins 197, 198 until the top left flange hinge rotation stop 116 comes into contact with the bottom left flange hinge rotation wall 166 and the top right flange hinge rotation stop 126 comes into contact with the bottom right flange hinge rotation wall 176. The contact between the hinge rotation stops 116, 126 and the hinge rotation walls 166, 176 prevents further rotation of the handgrip top 105 and handgrip bottom 150.

The pry structures 114, 124, 164, 174 are inset recesses into their respective flanges that form a cut-away portion of their respective flanges that are open to their respective top-to-bottom or bottom-to-top handgrip surface.

The grip structures 130, 180 may include a succession of raised areas and lowered areas so as to provide a better grip for a user.

Additionally, as shown in FIG. 1 , the exterior perimeters of the flanges 110, 120, 160, 170 include a plurality of flat regions 111-113, 121-123, 161-163, 171-173. When the handgrip 100 is in the closed position, the flat regions act as level surfaces to prevent the handgrip 100 from rolling. For example, depending on the position of the handgrip 100 relative to the floor, a pair of flat regions, such as the bottom left flange second flat region 162 and bottom right flange second flat region 172, may be parallel to the floor so that when the handgrip 100 is placed on the floor (or other flat surface), the flat regions 162, 172 contact the floor and the handgrip will be prevented from rolling.

In operation, the grip portion of a dumbbell is placed in the handgrip 100 in contact with the bottom foam engagement structure 190 of the handgrip bottom 150. The handgrip top 105 is then rotated to the closed position so that the top foam engagement structure 140 of the handgrip top 105 is also brought into contact with the grip portion of the dumbbell. As mentioned above, when the handgrip 100 is brought into the closed position, the top left flange magnet 119 is in magnetic engagement with the bottom left flange magnet 169 and the top right flange magnet 129 is in magnetic engagement with the bottom right flange magnet 179. This magnetic engagement provides a force to maintain the handgrip 100 in the closed position. The grip portion of the dumbbell maintains frictional engagement with the top foam engagement structure 140 and bottom foam engagement structure 190 to maintain the grip portion of the dumbbell within the handgrip 100.

When a user desired to remove the dumbbell from the handgrip 100, the pry structures 114, 125, 164, 174 are used when the handgrip 100 is in the closed position wherein the top-to-bottom handgrip surface 144 of the handgrip top 105 and the bottom-to-top handgrip contact surface 184 of the handgrip bottom 150 are in contact. As mentioned above, when in the closed position, the top left flange magnet 119 is in magnetic engagement with the bottom left flange magnet 169 and the top right flange magnet 129 is in magnetic engagement with the bottom right flange magnet 179. Thus, in order to rotate the handgrip top 105 and handgrip 150 away from each other out of the closed position, the magnetic engagement of the flange magnets must be overcome. In order to overcome the magnetic engagement of the flange magnets, the user manually interacts with one or more pairs of opposing pry structures, such as left top pry structure 114 and left bottom pry structure 164, to provide enough force to overcome the magnetic force provided by the magnets and induce the top-to-bottom handgrip surface 144 and bottom-to-top handgrip surface 184 to rotate away from each other. As shown in FIG. 1 , the pry structures may include an inset portion with a ledge or protrusion substantially parallel to the top-to-bottom handgrip surface when in the closed position.

In one embodiment, the magnetic force generated by the magnets 119, 129, 169, 179 is in the range of 5-10 lbs. The magnets may act as a safety feature to prevent the hinge from opening when it is undesired to do so. Additionally, in one embodiment, the magnets are positioned so that the face of the magnet is flush with the respective top-to-bottom handgrip surface 144 or bottom-to-top handgrip surface 184. In another embodiment, the magnets are positioned so that the face of the magnet is inset slightly from the respective top-to-bottom handgrip surface 144 or bottom-to-top handgrip surface 184 so that the magnets still exert a magnet attraction with their counterpart, but do not actually come into contact. This configuration may reduce corrosion or rust.

In one embodiment, the handgrip top 105 and/or the handgrip bottom 150 may be composed of cast steel, the top foam engagement structure 140 and full-width foam pad 191 may be composed of medium polyurethane foam, for example with a height of 1/16 of an inch, the first end pad 191 and second end pad 192 may be composed of ultrasoft polyurethane foam, for example with a height of ⅛ of an inch, and the magnets may be composed neodymium. The grip areas 130, 180 may comprise a firm central hollow tubular shape connecting the flanges. As described herein, the central hollow tubular shape allows the user to connect the handgrip top 105 and handgrip bottom 150 around a dumbbell handle positioned in the central hollow of the grip areas 130, 180.

In one embodiment, in the closed position, the combined top and bottom flanges of the handgrip 100 may be approximately 5 inches in height, 5.6 inches in width, 0.5 inches in thickness, and positioned about 4.8 inches apart parallel to the grip structure while the diameter of the grip composed of the top grip structure 130 and bottom grip structure 180 may be about 1.7 inches. The inner diameter formed between the top foam engagement structure 140 and the first end pad 191 and second end pad 192 may be about 0.7 inches. The magnets may be circular and approximately 0.20 inches in height and 0.25 inches in diameter. The flange hinge rotation stops may be about 0.25 inches in height.

FIG. 2 illustrates a right side view of the handgrip 100 of FIG. 1 in the closed position 200 according to an embodiment of the present invention. As discussed above, in the closed position 200, the handgrip top 105 has been rotated around the right hinge pin 198 hinge 195 so that the top-to-bottom handgrip surface 144 of the handgrip top 105 and the bottom-to-top handgrip contact surface 184 of the handgrip bottom 150 are in contact. As mentioned above, in the closed position the flange magnets in the handgrip top 105 are magnetically engaged with the flange magnets in the handgrip bottom 150. Additionally, FIG. 2 shows the bottom right flange hinge pin insert aperture 175 and bottom right flange hinge rotation wall 176 as well as the top right flange hinge rotation stop 126. The top right flange hinge pin insert aperture 125 is positioned along the right hinge pin 198 underneath the bottom right flange hinge pin insert aperture 175.

FIG. 3 illustrates a left side view of the handgrip 100 of FIG. 1 near the fully open position 300 according to an embodiment of the present invention. As discussed above, in the fully open position, the handgrip top 105 and handgrip bottom 150 are rotated around the hinge pins 197, 198 until the top left flange hinge rotation stop 116 comes into contact with the bottom left flange hinge rotation wall 166 and the top right flange hinge rotation stop 126 comes into contact with the bottom right flange hinge rotation wall 176. The contact between the hinge rotation stops 116, 126 and the hinge rotation walls 166, 176 prevents further rotation of the handgrip top 105 relative to the handgrip bottom 150. FIG. 3 shows the handgrip top 105 and handgrip bottom 150 rotates 180 degrees away from the closed position with the top left flange hinge rotation stop 116 about to come into contact with the bottom left flange hinge rotation wall 166 if rotation continued a few degrees further, such as 3 degrees, for example.

FIG. 4 illustrates a top view 400 of the handgrip 100 of FIG. 1 in the closed position according to an embodiment of the present invention. FIG. 4 shows the top left flange 110, the top right flange 120 of the handgrip top 105 as well as the top grip structure 130. The succession of raised areas 310 and lowered areas 320 that provides a better grip for a user is shown.

FIG. 5 illustrates a sectional view 500 of the handgrip of FIG. 4 sectioned between the indicators 5-5 shown in FIG. 4 . FIG. 5 shows the top left flange 110, bottom left flange 150, top left flange magnet insert aperture 117, top left flange magnet 119, bottom left flange insert aperture 167, and bottom left flange magnet 169. FIG. 5 additionally shows the top foam engagement structure 140 and bottom foam engagement structure 190 as well as the left hinge pin 197.

FIG. 6 illustrates a perspective view 600 of the handgrip of FIG. 1 with a dumbbell positioned in the handgrip according to an embodiment of the present invention. As shown in FIG. 6 , the handgrip top 105 has been rotated away from the handgrip bottom 150 using the handgrip hinge 195. This allows a dumbbell to be placed in the handgrip bottom 150 in the bottom foam channel 182 in contact with the bottom foam engagement structure 190. The handgrip top 105 is then rotated to the closed position as shown in FIG. 2 so that the grip of the dumbbell is brought into contact with the top foam engagement structure 140 positioned in the top foam channel 142. Additionally, as discussed above, in the closed position, the top left flange magnet 119 is in magnetic engagement with the bottom left flange magnet 169 and the top right flange magnet 129 is in magnetic engagement with the bottom right flange magnet 179.

FIG. 7 illustrates a front view 700 of the handgrip 100 of FIG. 1 with a dumbbell 720 positioned in the handgrip in the closed position.

In one embodiment, the handgrip 100 may be constructed to be a specific desired weight, such as 1.0 lb, 2.5 lbs, 5.0 lbs, or 7.5 lbs, for example. The weight of the handgrip may be varied, for example, by varying the material of which the handgrip is composed, including additional weighted material in the handgrip, or varying the dimensions of the handgrip somewhat, for example the height or one or more flanges. For example, one or more components of the handgrip may be composed of one or more of: Alloy Steel, Steel, Bismuth Tin Lead, Steel (1010—Low Carbon Steel), Steel (1018), Steel (A36—Structural Steel), Cast Iron, Black Oxide, Cold Black Oxide, Polyurethane Rubber, Rubber, Silicon Rubber, Plastic, and/or Polyurethane, each of which may have a differing density and thus may be combined to deliver a handgrip of a desired weight. Additionally, for example, the flanges may be composed partially of rubber and partially of steel—and the proportion of steel-to-rubber in the flange may be varied to deliver a handgrip of differing weights. Also, the width of one or more of the flanges and/or the grip structures 130 may be varied to allow a greater or lesser amount of material to be used in order to deliver handgrips of differing weights.

One or more embodiments of the present handgrip 100 may be used is several ways. First, for example, where the handgrip 100 is constructed to weigh 1.0 lb or 2.5 lbs, the handgrip may be used with pre-existing dumbbells to provide to the user a small but gradual increase in weight lifted. This allows the lifter to further challenge their body in small increments and may be helpful to maximize strength, efficiency, and or hypertrophy. For example, an experienced lifter who has been performing dumbbell curls using 30 lbs dumbbells, but is unable to transition immediately to 35 lbs dumbbells may instead use the present handgrip in conjunction with the 30 lbs dumbbell to deliver a total weight of 31 lbs. (in the case of a 1.0 lb handgrip) or 32.5 lbs. (in the case of a 2.5 lbs handgrip). This smaller increment of weight may allow the user to continue to make progress that may not otherwise have been possible.

As a second exemplary use for the present handgrip 100, one or more handgrips may be employed in order to reduce the total number of dumbbells that may need to be purchased while still providing users with a wide variety of options. For example, if a user possesses handgrips with weights of 2.5 lbs. 5.0 lbs. and 7.5 lbs. then the user may simply purchase five dumbbells with weights of 10 lbs. 20 lbs. 30 lbs. 40 lbs., and 50 lbs., but can use the handgrips to work out at any weight from 2.5 lbs. to 57.5 lbs. by either using the handgrips alone or by combining the handgrips with the five dumbbells. The user's set of 5 dumbbells and three handgrips can now provide the user with 23 different effective weights from 2.5 lbs. to 57.5 lbs., greatly lowering costs comparing to acquiring 23 different dumbbells. Additionally, the space requirements for storing the dumbbells would be greatly lessened.

As a third exemplary use for the present handgrip 100, it is well known that germs, including the COVID virus, may live on surfaces for a considerable length of time. Consequently, one methodology for reducing the spread of disease is to not touch surfaces that have been recently touched by many other people. Unfortunately, in a commercial gym setting, many different people may use the same dumbbells over the course of a day and the dumbbells are typically not cleaned between uses. Thus, a user may employ the present handgrip to avoid touching the actual handle of the dumbbell and consequently not expose themselves to any germs that may be present on the handle of the dumbbell.

In one embodiment, one or more of the top foam engagement structure and the bottom foam engagement structure may be in the shape of half-cylinder. Alternatively, some other arc of a cylinder may be employed such as 90 degrees. In another embodiment, the foam engagement structures are at least partially surrounded by their respective handgrip top or bottom.

While particular elements, embodiments, and applications of the present invention have been shown and described, it is understood that the invention is not limited thereto because modifications may be made by those skilled in the art, particularly in light of the foregoing teaching. It is therefore contemplated by the appended claims to cover such modifications and incorporate those features which come within the spirit and scope of the invention. 

1. A handgrip for use with a dumbbell, said handgrip including: a handgrip top including a top-to-bottom handgrip contact surface and at least partially surrounding a top foam engagement structure; a handgrip bottom including a bottom-to-top handgrip contact surface and at least partially surrounding a bottom foam engagement structure; and a handgrip hinge connecting said handgrip top and said handgrip bottom and allowing said handgrip top to rotate relative to said handgrip bottom so as to bring said top-to-bottom handgrip contact surface into contact with said bottom-to-top handgrip contact surface so that said top foam engagement surface and said bottom foam engagement surface engage with the handle of a dumbbell.
 2. The handgrip of claim 1 wherein said handgrip top includes a first flange.
 3. The handgrip of claim 2 wherein said handgrip top includes at least one additional flange connected to said first flange by a grip structure.
 4. The handgrip of claim 3 wherein at least one of said first flange and said at least one additional flange includes at least one flat region located on its exterior perimeter.
 5. The handgrip of claim 3 wherein at least one of said first flange and said at least one additional flange includes a pry structure.
 6. The handgrip of claim 3 wherein at least one of said first flange and said at least one additional flange includes a hinge rotation stop.
 7. The handgrip of claim 6 wherein at least one of said first flange and said at least one additional flange includes a hinge rotation wall.
 8. The handgrip of claim 1 wherein said top-to-bottom handgrip contact surface includes a first magnet and said bottom-to-top handgrip contact surface includes a second magnet.
 9. The handgrip of claim 8 wherein, when said top-to-bottom handgrip contact surface is in contact with said bottom-to-top handgrip contact surface, said first magnet and said second magnet are magnetically engaged.
 10. The handgrip of claim 3 wherein said grip structure includes a succession of raised and lowered areas.
 11. A method for securing a dumbbell in a handgrip, said method including: placing the handle of a dumbbell in contact with a bottom foam engagement structure of a handgrip bottom of a handgrip, wherein said handgrip bottom includes a bottom-to-top handgrip contact surface, wherein said handgrip bottom is connected to a handgrip top by a handgrip hinge, wherein said handgrip hinge allows said handgrip top to rotate relative to said handgrip bottom, wherein said handgrip top includes a top-to-bottom handgrip contact surface and at least partially surrounding a top foam engagement structure; and rotating said handgrip top relative to said handgrip bottom to bring said top-to-bottom handgrip contact surface into contact with said bottom-to-top handgrip contact surface, which also bring said top foam engagement structure into contact with said handle of said dumbbell.
 12. The method of claim 11 wherein said handgrip top includes a first flange.
 13. The method of claim 12 wherein said handgrip top includes at least one additional flange connected to said first flange by a grip structure.
 14. The method of claim 13 wherein at least one of said first flange and said at least one additional flange includes at least one flat region located on its exterior perimeter, wherein, when said handgrip is placed on a flat surface, said at least one flat region engages with said flat surface to prevent said handgrip from rolling.
 15. The method of claim 13 wherein at least one of said first flange and said at least one additional flange includes a pry structure, wherein said pry structure allows a user to apply force to induce said handgrip top away from said handgrip bottom.
 16. The method of claim 13 wherein at least one of said first flange and said at least one additional flange includes a hinge rotation stop, wherein said hinge rotation stop constrains the rotation of said handgrip top relative to said handgrip bottom.
 17. The method of claim 16 wherein at least one of said first flange and said at least one additional flange includes a hinge rotation wall, wherein said hinge rotation wall constrains the rotation of said handgrip top relative to said handgrip bottom.
 18. The method of claim 11 wherein said top-to-bottom handgrip contact surface includes a first magnet and said bottom-to-top handgrip contact surface includes a second magnet.
 19. The method of claim 18 further including magnetically engaging said top-to-bottom handgrip contact surface with said bottom-to-top handgrip contact surface using said magnets when said top-to-bottom handgrip contact surface and said bottom-to-top handgrip contact surface are in contact.
 20. The method of claim 13 wherein said grip structure includes a succession of raised and lowered areas. 